There are applications in the electronics art that require electrical connections between planes of separate planar electronics circuits. These circuits are commonly known as integrated circuits and include various active and passive electrical elements such as resistors, transistors, etc. The connections have heretofore been made by such means as descrete wiring or equivalent or by solder bumps. Discrete wiring usually requires that conductors on the boards be connected to edge connectors, to which multiple-connector jacks or sockets are connected. Individual wire or equivalent conductors between jacks or socket connectors thus provide the desired interconnection between boards. Obviously, this means wastes much circuit board area, introduces extra circuit impedances, is costly, and requires much room for jacks or sockets. A more efficient means in terms of space, cost, and impedance is solder bumps. In this technique, one of the circuit boards is masked, and bumps of a low-temperature solder are deposited through holes in the mask. The mask is then removed and the boards are placed with corresponding surfaces in accurately aligned contact. When a sufficient quantity heat is applied, the solder bumps melt and establish connections between the boards. This technique produces a circuit board sandwich that is susceptable to failures of the solder connections from unequal thermal expansion of the boards. Moreover, quite accurate initial alignment of the boards is required.
My invention overcomes the disadvantages of the means described above since it requires no masking steps, requires little if any, more space that solder bumps require, does not require as accurate alignment as solder bumps, needs no external or extra internal wires or connectors, and uses an adhesve flexible enough to withstand normal circuit board thermal movements.